Scarred Puma

A 2/1 for a single red mana is aggressive pricing, and Invasion paid for it by chaining the body to its multicolor theme: this Cat can swing only when a black or green creature joins the assault. That restriction is the whole conceit of the set's red-black and red-green archetypes, where committing to two colors was the cost of admission and a one-drop beater was the reward. The clause is harsher than it reads. It is not enough to control a black or green creature; that creature has to actually attack in the same combat, which means the Puma sits inert against any board state where your other threats need to hold back on defense, or where removal has stripped the right-colored attacker. Played alone, it is a wall that cannot block well. Played on curve in the deck it was built for, it is a turn-one clock that costs nothing to deploy. Wizards has returned to this template repeatedly (creatures that can't attack alone, that need a tribal or color companion in the red zone) as a way to push stats below the curve while taxing your deckbuilding rather than your mana. Scarred Puma is one of the earliest clean examples of the trade: the rate is a gift, and the gold-block requirement is the bill that comes due every combat step.